Authorities detained a Saudi woman on Saturday after she launched a campaign against the driving ban for women in the ultraconservative kingdom and posted a video of herself behind the wheel on Facebook and YouTube to encourage others to copy her.

Manal al-Sherif and a group of other women started a Facebook page called "Teach me how to drive so I can protect myself," which urges authorities to lift the driving ban. She went on a test drive in the eastern city of Khobar and later posted a video of the experience.

"This is a volunteer campaign to help the girls of this country" learn to drive, al-Sherif says in the video. "At least for times of emergency, God forbid. What if whoever is driving them gets a heart attack?"

Human rights activist Walid Abou el-Kheir said al-Sherif was detained by the country's religious police, who are charged with ensuring the kingdom's rigid interpretation of Islamic teachings are observed.

Al-Sherif was released hours later, according to the campaign's Twitter account. The terms of her release were not immediately clear.

Saudi Arabia is the only country in the world to ban women - both Saudi and foreign - from driving. The prohibition forces families to hire live-in drivers, and those who cannot afford the $300 to $400 a month for a driver must rely on male relatives to drive them to work, school, shopping or the doctor.